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46-510: The three brightest stars— Alpha , Beta and Nu Fornacis —form a flattened triangle facing south. With an apparent magnitude of 3.91, Alpha Fornacis is the brightest star in Fornax. Six star systems have been found to have exoplanets. The Fornax Dwarf galaxy is a small faint satellite galaxy of the Milky Way . NGC 1316 is a relatively close radio galaxy . The Hubble 's Ultra-Deep Field

92-508: A blue loop , but all stars with a degenerate core reach the tip with very similar core masses, temperatures, and luminosities. After the helium flash they lie along the ZAHB, all with helium cores just under 0.5  M ☉ and their properties determined mostly by the size of the hydrogen envelope outside the core. Lower envelope masses result in weaker hydrogen shell fusion and give hotter and slightly less luminous stars strung along

138-465: A blue straggler , and has likely accumulated material from a third star in the past. It is a strong source of X-rays and is 78% as massive as the Sun. Such a third star, designated Alpha Fornacis Bb, was detected in 2016. Alpha Fornacis Ba is enriched in barium relative to star A, suggesting that its companion is likely a white dwarf . Red clump The red clump is a clustering of red giants in

184-450: A degenerate helium core on the red-giant branch will ignite helium before the tip of the red-giant branch and perform a blue loop. For stars only a little more massive than the sun, around 2  M ☉ , the blue loop is very short and at a luminosity similar to the red clump giants. These stars are an order of magnitude less common than sun-like stars, even rarer compared to the sub-solar stars that can form red clump giants, and

230-419: A period of 1.89 days—the same as its rotational period. This is because of differences in abundances of metals in its atmosphere; it belongs to a class of star known as an Alpha Canum Venaticorum variable . Shining with an apparent magnitude of 5.89, Epsilon Fornacis is a binary star system located 104.4 ± 0.3 light-years distant from Earth. Its component stars orbit each other every 37 years. The primary star

276-611: A two-year stay at the Cape of Good Hope . He devised fourteen new constellations in uncharted regions of the Southern Celestial Hemisphere not visible from Europe. All but one honoured instruments that symbolised the Age of Enlightenment . Lacaille Latinised the name to Fornax Chimiae on his 1763 chart. The constellation Eridanus borders Fornax to the east, north and south, while Cetus, Sculptor and Phoenix gird it to

322-489: Is 2MASS 0243-2453 , a T-type brown dwarf of spectral type T6. With a surface temperature of 1040–1100 K , it has 2.4–4.1% the mass of the Sun, a diameter 9.2 to 10.6% of that of the Sun, and an age of 0.4–1.7 billion years. Six star systems in Fornax have been found to have planets: Local Group NGC 1049 is a globular cluster 500,000 light-years from Earth. It is in the Fornax Dwarf Galaxy. NGC 1360

368-437: Is 66 million light-years away from Earth. With a diameter of 130 000 light-years, it is one of the largest galaxies in the Fornax cluster and slightly larger than Milky Way . William Herschel discovered this galaxy on October 22, 1835. NGC 1386 is a spiral galaxy located in the constellation Eridanus . It is located at a distance of circa 53 million light years from Earth and has apparent dimensions of 3.89' x 1.349'. It

414-527: Is a Seyfert galaxy , the only one in Fornax Cluster . NGC 1427A is an irregular galaxy in the constellation Eridanus . Its distance modulus has been estimated using the globular cluster luminosity function to be 31.01 ± 0.21 which is about 52 Mly. It is the brightest dwarf irregular member of the Fornax cluster and is in the foreground of the cluster's central galaxy NGC 1399 . NGC 1460

460-410: Is a barred lenticular galaxy in the constellation Eridanus . It was discovered by John Herschel on November 28, 1837. It is moving away from the Milky Way 1341 km/s. NGC 1460 has a Hubble classification of SB0, which indicates it is a barred lenticular galaxy. But, this one contains a huge bar at its core. The bar is spreading from center to the edge of the galaxy, as seen on Hubble image in

506-576: Is a planetary nebula in Fornax with a magnitude of approximately 9.0, 1,280 light-years from Earth. Its central star is of magnitude 11.4, an unusually bright specimen. It is five times the size of the famed Ring Nebula in Lyra at 6.5 arcminutes. Unlike the Ring Nebula, NGC 1360 is clearly elliptical. The Fornax Dwarf galaxy is a dwarf galaxy that is part of the Local Group of galaxies. It

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552-473: Is a candidate protogalaxy located in Fornax, although recent analyses have suggested it is likely to be a lower redshift source. GRB 190114C was a notable gamma ray burst explosion from a galaxy 4.5 billion light years away near the Fornax constellation , that was initially detected in January 2019. According to astronomers, "the brightest light ever seen from Earth [to date] ... [the] biggest explosion in

598-493: Is a triple star system composed of a yellow giant and a pair of red dwarfs. R Fornacis is a long-period variable and carbon star. LP 944-20 is a brown dwarf of spectral type M9 that has around 7% the mass of the Sun. Approximately 21 light-years distant from Earth, it is a faint object with an apparent magnitude of 18.69. Observations published in 2007 showed that the atmosphere of LP 944-20 contains much lithium and that it has dusty clouds . Smaller and less luminous still

644-434: Is also a Seyfert galaxy . Its bar is a center of star formation and shows extensions of the spiral arms' dust lanes . The bright nucleus indicates the presence of an active galactic nucleus – a galaxy with a supermassive black hole at the center, accreting matter from the bar. It is a 10th magnitude galaxy associated with the Fornax Cluster . Fornax A is a radio galaxy with extensive radio lobes that corresponds to

690-399: Is around 12 billion years old and has cooled and expanded to 2.53 times the diameter of the Sun, while having only 91% of its mass. Omega Fornacis is a binary star system composed of a blue main-sequence star of spectral type B9.5V and magnitude 4.96, and a white main sequence star of spectral type A7V and magnitude 7.88. The system is 470 ± 10 light-years distant from Earth. Kappa Fornacis

736-765: Is located within the Fornax constellation. It is the 41st largest constellation in the night-sky , occupying an area of 398 square degrees. It is located in the first quadrant of the southern hemisphere (SQ1) and can be seen at latitudes between +50° and -90° during the month of December. The French astronomer Nicolas Louis de Lacaille first described the constellation in French as le Fourneau Chymique (the Chemical Furnace) with an alembic and receiver in his early catalogue, before abbreviating it to le Fourneau on his planisphere in 1752, after he had observed and catalogued almost 10,000 southern stars during

782-403: Is not visible in amateur telescopes, despite its relatively small distance of 500,000 light-years. Helmi stream is a small galactic stream in Fornax. This small galaxy was destroyed by Milky Way 6 billion years ago. There was candidate for extragalactic planet, HIP 13044 b. Outside NGC 1097 is a barred spiral galaxy in Fornax, about 45 million light-years from Earth. At magnitude 9, it

828-464: Is now so included in the List of IAU-approved Star Names. Alpha Fornacis has a high proper motion and the system displays an excess of infrared emission , which may indicate the presence of circumstellar material such as a debris disk . The space velocity components of this star are (U, V, W) = (−35, +20, +30) km/s. Approximately 350,000 years ago, Alpha Fornacis experienced a close encounter with

874-458: Is visible in medium amateur telescopes. It is notable as a Seyfert galaxy with strong spectral emissions indicating ionized gases and a central supermassive black hole . Fornax Cluster The Fornax Cluster is a cluster of galaxies lying at a distance of 19 mega parsecs (62 million light-years ). It is the second richest galaxy cluster within 100 million light-years, after the considerably larger Virgo Cluster , and may be associated with

920-401: Is weaker in low metallicity stars, so the red clump is usually more prominent in metal-rich clusters. However, there are other effects, and there are well-populated red clumps in some metal-poor globular clusters. Stars with a similar mass to the sun evolve towards the tip of the red-giant branch with a degenerate helium core. More massive stars leave the red-giant branch early and perform

966-524: The A-type main-sequence star Nu Horologii . The two came within an estimated 0.265 ly (0.081 pc) of each other, and both stars have debris disks. Alpha Fornacis A has a stellar classification of F8IV, where the luminosity class IV indicates this is a subgiant star that has just evolved off the main sequence . It has 33% more mass than the Sun and is an estimated 2.9 billion years old. The secondary, Alpha Fornacis B, has been identified as

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1012-479: The Hertzsprung–Russell diagram at around 5,000 K and absolute magnitude (M V ) +0.5, slightly hotter than most red-giant-branch stars of the same luminosity. It is visible as a denser region of the red-giant branch or a bulge towards hotter temperatures. It is prominent in many galactic open clusters , and it is also noticeable in many intermediate-age globular clusters and in nearby field stars (e.g.

1058-535: The Hipparcos mission, it is approximately 46 light-years (14 parsecs ) distant from the Sun . Its three components are designated Alpha Fornacis A (officially named Dalim / ˈ d eɪ l ɪ m / ), Alpha Fornacis Ba and Alpha Fornacis Bb . α Fornacis ( Latinised to Alpha Fornacis ) is the system's Bayer designation . The designations of the three components as Alpha Fornacis A, Ba and Bb derive from

1104-461: The Hipparcos stars ). The red clump giants are cool horizontal branch stars, stars originally similar to the Sun which have undergone a helium flash and are now fusing helium in their cores. Red clump stellar properties vary depending on their origin, most notably on the metallicity of the stars, but typically they have early K spectral types and effective temperatures around 5,000 K. The absolute visual magnitude of red clump giants near

1150-710: The Royal Astronomical Society in Britain , a team from University of Queensland described 40 unknown "dwarf" galaxies in this constellation; follow-up observations with the Hubble Space Telescope and the European Southern Observatory 's Very Large Telescope revealed that ultra compact dwarfs are much smaller than previously known dwarf galaxies, about 120 light-years (37 pc) across. ` UDFj-39546284

1196-478: The equatorial coordinate system , the right ascension coordinates of these borders lie between 01 45 24.18 and 03 50 21.34 , while the declination coordinates are between −23.76° and −39.58°. The whole constellation is visible to observers south of latitude 50°N . Lacaille gave Bayer designations to 27 stars now named Alpha to Omega Fornacis, labelling two stars 3.5 degrees apart as Gamma, three stars Eta, two stars Iota, two Lambda and three Chi. Phi Fornacis

1242-405: The "red bump" or red-giant-branch bump, which is a less noticeable clustering of giants partway along the red-giant branch , caused as stars ascending the red-giant branch temporarily decrease in luminosity because of internal convection. Many of the bright "red giants" visible in the sky are actually G or early K class red-clump stars. Pollux , the closest red giant to the Sun, is believed to be

1288-460: The Sun's diameter, 178 ± 2 light-years from Earth. It is a red clump giant, which means it has undergone helium flash and is currently generating energy through the fusion of helium at its core. Nu Fornacis is 370 ± 10 light-years distant from Earth. It is a blue giant star of spectral type B9.5IIIspSi that is 3.65 ± 0.18 times as massive and around 245 times as luminous as the Sun, with 3.2 ± 0.4 times its diameter. It varies in luminosity over

1334-438: The Sun's radius. Of magnitude 6.5, the secondary star is 0.78 times as massive as the Sun. It has been identified as a blue straggler , and has either accumulated material from, or merged with, a third star in the past. It is a strong source of X-rays. The pair is 46.4 ± 0.3 light-years distant from Earth. Beta Fornacis is a yellow-hued giant star of spectral type G8IIIb of magnitude 4.5 that has cooled and swelled to 11 times

1380-691: The Universe since the Big Bang ". In Chinese astronomy , the stars that correspond to Fornax are within the White Tiger of the West (西方白虎, Xī Fāng Bái Hǔ ). Alpha Fornacis Alpha Fornacis ( α Fornacis , abbreviated Alpha For , α For ) is a triple star system in the southern constellation of Fornax . It is the brightest star in the constellation and the only one brighter than magnitude 4.0. Based on parallax measurements obtained during

1426-410: The box. This bar is one of the largest seen in barred lenticular galaxies. There are also first ultracompact dwarf galaxies discovered. Distant universe Fornax has been the target of investigations into the furthest reaches of the universe . The Hubble Ultra Deep Field is located within Fornax, and the Fornax Cluster , a small cluster of galaxies , lies primarily within Fornax. At a meeting of

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1472-728: The convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems , and adopted by the International Astronomical Union (IAU). Formerly it was designated as the 12th of Eridanus (12 Eri) by Flamsteed . Indigenous Arabs had named both Alpha Eridani and Fomalhaut ظَلِيم al-ẓalīm , a local word for 'ostrich'. Later, Arabian astronomer would transfer the appellation to Theta Eridani , as they could not see those other stars from their location. In recent times, Italian astronomer Giuseppe Piazzi applied it with

1518-469: The duration of the blue loop is far less than the time spent by a red clump giant on the horizontal branch. This means that these imposters are much less common in the H–R diagram, but still detectable. Stars with 2–3  M ☉ will also pass through the red clump as they evolve along the subgiant branch . This is again a very rapid phase of evolution , but stars such as OU Andromedae are found in

1564-531: The effects are much smaller in the infrared. Near infrared I band observations in particular have been used to establish red clump distances. Absolute magnitudes for the red clump at solar metallicity have been measured at −0.22 in the I band and −1.54 in the K band . The distance to the Galactic Center has been measured in this way, giving a result of 7.52 kpc in agreement with other methods. The red clump should not be confused with

1610-455: The horizontal branch. Different initial masses and natural variations in mass loss rates on the red-giant branch cause the variations in the envelope masses even though the helium cores are all the same size. Low-metallicity stars are more sensitive to the size of the hydrogen envelope, so with the same envelope masses they are spread further along the horizontal branch and fewer fall in the red clump. Although red clump stars lie consistently to

1656-460: The hot side of the red-giant branch that they evolved from, red clump and red-giant-branch stars from different populations can overlap. This occurs in ω Centauri where metal-poor red-giant-branch stars have the same or hotter temperatures as more metal-rich red clump giants. Other stars, not strictly horizontal branch stars, can lie in the same region of the H-R diagram. Stars too massive to develop

1702-450: The nearby Eridanus Group . It lies primarily in the constellation Fornax, with its southern boundaries partially crossing into the constellation of Eridanus, and covers an area of sky about 6° across or about 28 sq degrees. The Fornax cluster is a part of larger Fornax Wall . Down are some famous objects in this cluster: NGC 1365 is another barred spiral galaxy located at a distance of 56 million light-years from Earth. Like NGC 1097, it

1748-441: The north, west and south respectively. Covering 397.5 square degrees and 0.964% of the night sky, it ranks 41st of the 88 constellations in size, The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is "For". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 8 segments ( illustrated in infobox ). In

1794-443: The optical galaxy NGC 1316 , a 9th-magnitude galaxy. One of the closer active galaxies to Earth at a distance of 62 million light-years, Fornax A appears in the optical spectrum as a large elliptical galaxy with dust lanes near its core. These dust lanes have caused astronomers to discern that it recently merged with a small spiral galaxy . Because it has a high rate of type Ia supernovae , NGC 1316 has been used to determine

1840-418: The presence of other stars with similar properties. Although red clump stars are generally hotter than red-giant-branch stars, the two regions overlap and the status of individual stars can only be assigned with a detailed chemical abundance study. Modelling of the horizontal branch has shown that stars have a strong tendency to cluster at the cool end of the zero age horizontal branch (ZAHB). This tendency

1886-598: The red clump region (5,500 K and 100  L ☉ ) even though it is thought to be a subgiant crossing the Hertzsprung gap . In theory, the absolute luminosities of stars in the red clump are fairly independent of stellar composition or age so that consequently they make good standard candles for estimating astronomical distances both within our galaxy and to nearby galaxies and clusters. Variations due to metallicity, mass, age, and extinctions affect visual observations too much for them to be useful, but

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1932-439: The shallow southern apex. Originally designated 12 Eridani by John Flamsteed, Alpha Fornacis was named by Lacaille as the brightest star in the new constellation. It is a binary star that can be resolved by small amateur telescopes. With an apparent magnitude of 3.91, the primary is a yellow-white subgiant 1.21 times as massive as the Sun that has begun to cool and expand after exhausting its core hydrogen, having swollen to 1.9 times

1978-468: The size of the universe. The jets producing the radio lobes are not particularly powerful, giving the lobes a more diffuse, knotted structure due to interactions with the intergalactic medium . Associated with this peculiar galaxy is an entire cluster of galaxies. NGC 1399 is a large elliptical galaxy in the Southern constellation Fornax , the central galaxy in the Fornax cluster . The galaxy

2024-502: The spelling Dalim to his "III 13" (= α For) in his Palermo Catalogue , and Elijah Burritt labeled it Fornacis in his Atlas . In 2016, the IAU organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems . It approved the name Dalim for the component Alpha Fornacis A on 5 September 2017 and it

2070-403: The sun has been measured at an average of +0.81 with metallicities between −0.6 and +0.4 dex. There is a considerable spread in the properties of red clump stars even within a single population of similar stars such as an open cluster. This is partly due to the natural variation in temperatures and luminosities of horizontal branch stars when they form and as they evolve, and partly due to

2116-508: Was added by Gould, and Theta and Omicron were dropped by Gould and Baily respectively. Upsilon, too, was later found to be two stars and designated as such. Overall, there are 59 stars within the constellation's borders brighter than or equal to apparent magnitude 6.5. However, there are no stars brighter than the fourth magnitude. The three brightest stars form a flattish triangle, with Alpha (also called Dalim) and Nu Fornacis marking its eastern and western points and Beta Fornacis marking

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